Torpedo exploder



Jan. 29, 1957 R. E. SMITH 2,779,277

TORPEDO EXPLODER Filed Dec. 3, 1946 2 Sheets-Sheet 1 Jan. 29, 1957 $M|TH 2,779,277

TORPEDO EXPLODER Filed D90. 3, 1946 2 SheetsSheet 2 United States Patent TORPEDO EXPLODER Robert E. Smith, Washington, D. C. Application December 3, 1946, Serial No. 713,729

7 Claims. (c1. 102-16) (Granted under Title 35, U. S. Code (1952), see. 266) This invention relates to an exploder mechanism for a torpedo and more specifically to a torpedo exploder in which the firing is accomplished by sudden movement of a coil disposed within a magnetic circuit sufficient to fire a low energy detonating device upon impact of the torpedo with a target.

In torpedo exploders of the type heretofore devised considerable difficulty has been experienced by failure of the torpedo to explode as it strikes the target or by premature firing of the torpedo due to pitch and roll or broaching during the travel of the torpedo through the water.

The device of the present invention retains all of the advantages of the devices of this class heretofore devised and possesses none of the foregoing disadvantages.

In the device of the present invention, the firing of the torpedo is accomplished by a sudden movement of a movable coil from an initial position of rest Within a strong magnetic field thereby to generate an electrical signal of sufficient strength to fire a low energy detonator as the torpedo strikes the target regardless of the angle of impact of the torpedo with the target.

' One of the objects of the present invention is to provide a new and improved exploder for a torpedo.

Another object is to provide. an electromagnetic exploder for a torpedo in which new andimproved means are employed for generating an electrical firing impulse as the torpedo strikes the target. I

Still another object is to provide a new and improved electromagnetic exploder which is adapted to be employed with a torpedo of conventional design without material modification of the torpedo.

Still other objects, advantages and improvements will be apparent from the following description, taken in connection with the accompanying drawings of which:

Fig. l is a view partially in section of a torpedo employing the device of the present invention in accordance with a preferred embodiment thereof;

Fig. 2 is an elevational view somewhat enlarged and partially-in section of the inertia generator of Fig. 1; and

a Fig. 3 is a diagrammatic view of the torpedo exploder of the present invention in an armed condition.

Referring now to the drawings on which like numerals of reference are employed to designate like parts throughout the several views and more particularly to Fig. 1 thereof, there is shown thereon a torpedo indicated generally by the numeral 14} comprising a casing 11 provided with the usual hand hole 12 in the nose portion thereof. Fitted within the hand hole is a torpedo arming mechanism indicated generally by the numeral 13 and secured thereto in any convenient manner as by the bolts 15, a gasket 16 being provided to insure a watertight seal therebetween. The torpedo arming mechanism may be of any type suitable for the purpose such, for example, as the torpedo arming mechanism described and claimed in thecopending application of I. M. Kendall et al. for Torpedo Exploder Mechanism, Serial No. 750,615, filed worm wheel 50, Fig. 3.

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May 26, 1947, the mechanism comprising a chamber 17 having a water inlet 18 and an outlet 19 arranged to cause a flow of water therethrough as the torpedo travels through the water on a run toward the target. Within the chamber is rotatably mounted an impeller 21 adapted to be rotated by the aforesaid flow of water and through suitable gearing indicated generally at 22 and 23 causes a shaft 24 to rotate slowly from an initial position to a final position during the travel of the torpedo through the water. The shaft carries a worm 4-0 which drives a The rotation of the shaft causes an element 25 of the explosive train of the exploder carried by wheel 50 to be moved from an initial safe position to an armed position in operative relation with a tetryl pellet 20 communicating with a booster charge within the casing 26 and in operative relation with a low energy detonator or squib 30. The explosion of the booster charge causes the main charge 27 within the torpedo to be fired. There is also provided an arming switch 28 adapted to close a firing circuit when the shaft 24 has made a predetermined degree of rotative movement during the travel of the torpedo toward the target such that a cam 61 carried by wheel 50 moves into a position to close switch 28. As the torpedo strikes the target, the firing circuit is energized by an electrical impulse received from an inertia controlled voltage generating mechanism indicated generally by the numeral 29 and secured to the arming mechanism 13 in any suitable manner as by the support 31 with the axis of the device preferably arranged in the direction of the line of travel of the torpedo as illustrated.

The voltage generating mechanism 29, Fig. 2, comprises a pot magnet 32 composed of any material suitable for the purpose and having a bore 33 therein within which is fitted a pole piece 34 preferably composed of material having magnetic properties similar to those ofsoft iron. The pole piece 34 is generally cylindrical in shape and provided-with a circular flanged portion 35 for engagement with the bore 33 of the pot magnet whereby the pole piece is secured to the pot magnet in concentric relation therewith. The polepiece 34 is also provided with a cylindrical portion 36 of reduced diameter and a head 37 of somewhat greater diameter contiguous therewith, the head'having a cylindrical periphery in concentric spaced relationship with respect to the bore 33.

It will now be apparent from the foregoing description that the pot magnet 33 sets up a magnetic circuit which includes the .pole piece 34'and the annular gap between 'the head 37 thereof and the bore 33 of the magnet such that themagnetic field of the magnet is highly concentrated within the gap adjacent the cylindrical periphery of the head. The pole piece 34 is also provided with a centrally disposed bore 38 having end portions 39 thereof of greater diameter than the central portion of the bore. Within'the bore 38 is arranged a plunger or rod 41 preferably composed of nonmagnetic material and threaded at 42 m receive a pair of locking nuts 43. Within the 7 end portions 39 respectively of the bore 38 are secured a pair of bearings 44 and 45 adapted to support the plunger 41 for reciprocal movementwithin the 'bore, bearing 44 having a bearing surface therein for engagement with. an enlarged cylindrical portion 46 of the rod. A shoulder is provided on the rod between the portion 46 thereof and the central portion of the rod in abutting relation with a washer .47. A resilient spring48 is disposed within the bore 38 and in engagement with the washer 47 and the bearing 45, the tension of the spring being adjustable by the nuts 43. A washer 49 is preferably provided between the nuts 43 and bearing 45.

A cup-shaped spool 51 composed of nonmagnetic material is secured to the plunger 41 by a nut 52 threaded thereon, a pair ofxwashers 54 being preferably arranged on opposite sides of the end portion of the spool in abutting relation with the enlarged cylindrical portion 46' of the arming switch 28 and an additional conductor 61.

The switch 28, it will benoted, is normally open and premature movement of the coil 57 .Within the magnetic field set up" by themagnet 32 prior to closure of the arm-V,

ingjswitch will be inefiective to fire the detonator. When the torpedo has traveled a predetermined distance through the ;water, however, the armingswitch is closed and the circuit is completed between the coil 57 and the detonator. This circuit, herein. referred to as a firing circuit, is not energized until the torpedo strikes the target, the coil57 being held'immovable with respect to the magnetic fieldset up by the magnet 32 by reason of the force of the spring 48 against thev washer 47, the tension in the spring being calibrated to a predetermined value by adjustment-of nuts 43 such that forces corresponding to accelerationsless than seven timesgravity, for example, will not cause movement of the coil. Thus, during the travel'of the torpedo through the Water the coil does not move regardless of the pitch and yaw of the torpedo or whether the torpedo should broach during the torpedo run.

As the torpedo strikes the target, the coil 57' is suddenly moved inwardly Within the bore 33 and the number of flux linkages of the'coil with the field set up by the magnet 32, is suddenly increased. When thisoccurs, the ,coil generates a voltage of sufficient strength to cause a current flow to fire the detonator 30 and explode the torpedo regardless of theangle of inpact of the torpedo with the vesselqxw V V a a 7 While the'invention has been described with reference to a particular example thereof which gives satisfactory results, it will be understood'by those skilled in the art towhich the invention pertains, after understanding the invention, that various changes'and 'modifications'may be made Without departing from the spirit and scope of the invention, and it is intended, therefore, 'in the appended claims tocover all such changes and modifications.

The-invention herein described and claimed may be manufactured and used by or for the Government of the United States of America for governmentalpurposes without'payment' of any royalties thereon or therefor.

What is claimed as new and desired to be" secured by Letters Patent of the United States is: 1 V

l. A torpedo exploder of the character disclosed for usein' a torpedorcomprising, in combination, 'afiring circuit including an electroresponsive squib, fluid driven arming means for closing said circuit during the opera- I tion of said means,,and electromagnetic means connected in said firing circuit and adapted to generate a current for firing said squib, said electromagnetic means comprising a'permanent magnet provided with a longitudinal bore substantially parallel to the longitudinalaxis of the torpedo, bearing members mounted within said bore, a plunger resiliently mounted within the bore for longitudinal sliding movement onsaidlbearings', and a.coil rigidly connected to said plunger and adapted to be moved within the field of said permanent magnet in response to impact of the torpedo with its target, a coil, spring disposed within said bore and maintained undercompression by said bearing members said1springbeingsleeved on the plunger for normally biasing and supporting the plunger and coil to an initial position withinthe field. of the magnet.

2. A torpedo exploder of the character disclosed comprising, in combination, a firing circuit, an electroresponsive squib included in said circuit, and electromagnetic means connected in said firing circuit and adapted to gencrate a current for firing said squib, said electromagnetic means comprisinga substantially cylindrical permanent magnet provided with a longitudinal how, an inertia responsive coil, a plunger;slidably mounted within said bore and rigidly connected to said coil for moving the coil within the field of said magnet as the torpedo strikes its target, a coil spring undercompression disposed within said bore and sleeved to the plunger for normally biasing and supporting the plunger and inertia coil to an initial position within the field of the magnet, and adjustable means mounted on said plunger for varying the tension of said spring.

3. in a torpedo, the combination of an explosive train including an, element initially positioned out of operative relation with respect thereto, means including an element responsive to the movement of the torpedo through the water for moving said element into operative relation with respect tothe explosive train, an initially open firin'g circuit, switch means controlled by said last named means for closing said firing circuit, electroresponsive detonating means connected in the firing circuit for firing the explosive charge of the torpedo through said explosive train, and electromagnetic means also connected .in the firing circuit and adapted to generate a voltage for firing said detonating means in response to the impact of the torpedo with its target, said electromagnetic means including a magnet'having a longitudinal bore therein, a plunger slideably mounted within said bore, a spring sleeved-on said plunger under compression and disposed within said bore for biasing and supporting the plunger toward a'n'ormal position thereof, adjustable means on the plunger for varying the tension of said spring, and an induction coil fixed to the plunger for movement therewith and within the field of said magnet.

4. In a torpedo, a firing circuit, a normally incomplete detonating train, electroresponsive means connected in said firing circuit for initiating the detonation of the explosive charge of the torpedo through said detonating train, an arming switch in said firing circuit, means for completing said detonator train and for closing said arming switch, and electromagnetic means also connected in said firingcircuit, said electromagnetic means comprising a sleeve-like permanent magnet and a soft iron core adapted to .close one end of the sleeve, said core having ahead disposed in spaced relation with the inner wall of they other end of the sleeve to provide a peripheral air gap therebetwecn within which the field of the magnet is highly concentrated, said core having a central boreconcentrically disposed with respect to said sleeve, a plunger rod having a shoulder and mounted for reciprocal movement within said bore, a coil carried by said rod at one end thereof, acoil spring sleeved on the rod and interposed under compression between the core and said shoulder on the rod wherebythe coil is urged yieldably into an initial position of rest within said gap, and adjustable means carried at the'other end of the rod for varying the tension in said spring whereby the coil is adapted to traverse the field in'saidair gap as the rod moves reciprocally within the' bore in response to the impact of the torpedo with theflta'rget thereby to. generate a voltage for firing said electroresponsive means. ,l V l '5. In a torpedo, a firing circuit, a normally incomplete detonator train, electroresponsive means connected in said firing circuit for initiating the detonation of the explosive charge of the torpedo through said detonating train, an' arming, switch; in said firing circuit, means for completing said detonator'trainjand for closing said arming switch, and electromagnetic means also connected in said firing-circuit, said electromagnetic means comprising a permanent magnet having an air gap and a centrally disposed longitudinal bore, a plunger slideably mounted in said bore, and a coil connected to said plunger for movement within the air gap portion of the field of the permanent magnet in response to a force suddenly applied thereto, a spring sleeved on said plunger under compression for biasing and supporting said coil to an initial position of rest within the field of said permanent magnet, bearing means on said plunger and the permanent magnet in engagement with said spring for maintaining the spring under compression, and adjustable means mounted on the plunger for varying the tension of the spring.

6. An inertia generator of the character disclosed comprising, in combination, a pot magnetic structure including a sleeve-like permanent magnet and a soft iron core adapted to close one end of the sleeve, said core having a head disposed in spaced relation with the inner wall of the other end of the sleeve to provide a peripheral air gap therebetween within which the field of the magnet is highly concentrated, said core having a central bore concentrically disposed with respect to said sleeve, a plunger rod having a shoulder and mounted for reciprocal movement within said bore, a coil carried by said rod at one end thereof and adapted to traverse the field in said air gap as the rod moves reciprocally within the bore, a coil spring sleeved on'the rod and interposed under compression between the core and said shoulder on the rod whereby the coil is urged yieldably into an initial position of rest within said gap, and adjustable means carried at the other end of the rod for varying the tension in said spring.

7. An inertia generator of the character disclosed comprising, in combination, means for setting up a highly concentrated magnetic field of annular cross section, said means having a longitudinal bore, a plunger having a shoulder and slideably mounted in said bore, an induction coil mechanically connected to said plunger and posi- References Cited in the file of this patent UNITED STATES PATENTS 2,316,616 Powell Apr. 13, 1943 2,400,100 Byrnes et al. May 14, 1946 FOREIGN PATENTS 1,089 Great Britain Jan. 13, 1912 506,280 France May 26, 1920 557,110 France Apr. 27, 1923 525,333 Great Britain Aug. 27, 1940 OTHER REFERENCES Electronics" Magazine, pp. 98-103, December 1945 (McGraw-Hill Pub. Co. Inc., 99-129 N. Broadway,

. Albany 1, N. Y.), 

